Methods

A two step literature search was conducted between January and March 2008. The MedlineÂ® data base was used for the initial literature search. The combination of the keywords “Guangdong” or “Pearl River Delta” or “Guangzhou” and pollut* provided 200 references. 48 of them were identified to deal with anthropogenic ambient aerosol pollution in the considered region. Based on their abstracts, 17 studies were selected for further analysis. In the second step, the reference lists of the 17 papers were examined for further studies according to the review protocol.

Results

Finally, 34 studies were thoroughly scrutinised resulting in 15 studies that reported aerosol burden measured since 2000 in PRD. Almost all of the studies reported levels of annual mean PM10 clearly exceeding the WHO Air Quality Guidelines (AQG) of 20 Âµg/m3 and the Chinese Ambient Air Quality Standards (40Âµg/m3 annual mean). PM2.5 data were less frequently reported and exceeded AQG (10Âµg/m3 annual and 25Âµg/m3 daily) and the United States’ National Ambient Air Quality Standards (15Âµg/m3 annual and 35Âµg/m3 daily) by far.

Discussion

Taking into account that a number of Chinese cities such as Beijing, Shanghai or Guangzhou in PRD have some of the world’s highest recorded outdoor PM10 levels [Ref.Â 4], [Ref.Â 10], and that our results show that almost all data clearly exceed national and international air quality guidelines, high burden of aerosol-related diseases can be expected in PRD. Further epidemiological studies should be carried out to determine more precisely the spatial distribution of aerosol-related health risks in PRD. Environmental protection measures and public health interventions are required to reduce aerosol-related burden of disease in PRD.